Cooling device for electronic components

ABSTRACT

The refrigeration device for electronic components features a plate that is equipped on both sides with heat exchanger elements ( 22 ), along whose surface two separate air stream paths are disposed, of which one guides external air and one internal air. The refrigeration device features two intakes ( 15, 16 ), which lie in one plane, that are in a flow connection with two separated chambers ( 19, 20 ). Furthermore the two chambers are in an air stream connection by means of guiding plates ( 25, 26 ) with channels ( 23, 24 ) on the upper- and lower side of the plate.

REFERENCE TO RELATED APPLICATIONS

This application claims priority to German application 202008003516.3filed 12 Mar. 2008.

FIELD OF THE INVENTION

The invention concerns a refrigeration device for electronic componentsaccording to the preamble of the patent claim 1.

BACKGROUND OF THE INVENTION

Such a refrigeration device is known from DE 10 2004 030 675 A1. There arefrigeration installation is described for electronic components thatfeature a mounting plate to which electronic components are attached inheat-conducting contact. To the mounting plate several heat exchangerelements are attached. The mounting plate forms thereby the back wall ofa switch box and is covered by means of a cover so that a flow channelforms that is located outside the interior space of the switch box andto which external air is guided by means of a blower. In the interiorspace an additional air stream can be generated along the mounting plateby means of convection or an additional blower.

Furthermore it is proposed there to utilize special heat exchangerelements such as they are described in DE 102 33 736.

These known refrigeration installations work in principle with anair/air heat exchange, whereby one assumes that the exterior air iscolder than the interior air in the interior space of the switch box. Asis well known, the heat exchange in a heat exchanger depends verysignificantly on the temperature difference of the media that are inheat exchange with one another. As a result the cooling performance ofthe known installations is not satisfactory in the case of high externaltemperatures.

As part of prior art active refrigeration installations that workaccording to the principle of a refrigerator with a compressor or with aPeltier element (compare U.S. Pat. No. 5,706,668) are therefore alsoalready known As an example DE 10 2006 034 487 A1 describes a heatexchanger with Peltier elements that are on both sides in aheat-exchanging contact with heat releasing and heat absorbing elements,whereby respectively a fluid heating and a fluid cooling channel abutsagainst the heat releasing and heat absorbing elements.

Refrigeration installations with Peltier elements are also described inDE 10 2006 020 502 and 10 2006 020 503, DE 10 2006 020 499, DE 299 21448 U1, and DE 203 01 232 U1.

The DE 201 05 487 U1 describes a refrigeration device with Peltierelements whereby a switch-over between individual cooling modes ispossible, depending on the surrounding temperature, due to the fact thatthe Peltier elements can be switched either all in parallel, orgroup-wise or as a whole in series, whereby the cooling performance iscontrollable by simple means.

The DE 200 07 920 U1 describes a blower apparatus for a housing withPeltier elements whereby the air stream can be reversed in a selectablemanner in order to switch between cooling and heating operation.

Peltier elements are obtainable today as flat platelets withheat-releasing and heat-absorbing side. Of a disadvantage is of coursetheir consumption electrical energy and the problem that the efficiencyor the cooling performance is temperature-dependent and diminishes withincreasing temperature difference between heat-absorbing side andheat-releasing side.

SUMMARY OF THE INVENTION

It is the purpose of the invention to improve the air conditioningdevice of the type referred to above insofar that it maintains thetemperature of electronic components well within a prescribedtemperature range over a large temperature range of the externaltemperature, that is features a high power density, is as compact aspossible, and features a low consumption of electrical energy.

The problem is solved according to the characteristics indicated inpatent claim 1. Advantageous embodiments and improvements of theinvention can be deduced from the sub-claims.

The basic principle of the invention is to implement the refrigerationdevice as a compact device with Peltier elements that are provided onboth sides with heat-exchanger elements, whereby the device features twoair intakes and two air exhausts that are connected with two separatedflow paths, of which one runs along one side of the Peltier element andone runs along on the other side of the Peltier element. The two intakeslie preferably parallel in one plane, whereby with each intake aventilator is associated that guides the entering air from a intakespace across guiding plates to the corresponding air stream path on theupper or lower side of the Peltier element.

The device is preferably adapted to norm switch boxes with 19 inchtracks and features a height of only one height unit, corresponding to44.45 mm, a width of 448 mm, and a depth of 480 mm.

The device can work as a pure circulation installation that draws in thecool external air through slits or openings of a switch box andcirculates it in the interior space of the switch box. If increasedcooling performance is required the Peltier element can be switched intoactive mode and work thereby as an active chiller. The Peltier elementcan contain, taking the measures described above into account, up to 27individual elements that each feature a power of 10 to 15 Watt per unitso that a cooling power of 270 to 405 Watt is possible.

In the case of the circulation operation mentioned first one of theventilators can also be turned off.

In summary, one therefore obtains a hybrid refrigeration device of lowinstallation height and high power density. By means of the twooperation modes the consumption of electrical energy can be economized.The device can be installed in different directions in a switch box sothat the cooling air can be blown out upward or downward.

BRIEF DESCRIPTION OF THE DRAWINGS

In what follows the invention is explained in more detail based on anembodiment example in connection with the drawing. It is shown:

FIG. 1, a perspective representation of a partially cut switch box witha refrigeration device according to the invention;

FIG. 2, a perspective, schematic representation of the refrigerationdevice according to the invention;

FIG. 3, a schematic top view of an opened refrigeration device accordingto the invention;

FIG. 4, a cut along the line A-A of FIG. 3; and

FIG. 5, a cut along the line B-B of FIG. 3.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

FIG. 1 presents a conventional switch box 1 (without door) that featureslateral tracks 2 and 3 for the sliding-in and retaining of electricaland electronic components, as well as vertical carriers 4, 5, 6, and 7,to which external walls are attached, whereby two of the carriers, inthis case carriers 4 and 6, feature rows of boreholes 8 and 9 for theattachment of components to be slid in. On the carriers 6 and 7corresponding rows of boreholes can also be provided.

The refrigeration device according to the invention is implemented as aslide-in element that is adapted to the dimensions of such norm switchbox. It for example features the dimensions mentioned above if it isutilized in a 19 inch switch box. The refrigeration device in itsentirety is labeled with the reference symbol 10. By means of twolateral flaps 11 and 12 that feature holes 13 and 14 it can be attachedat the carriers 4 and 6 and the rows of boreholes there, whereby it isheld to the tracks 2 and 3.

As can be discerned from FIG. 2, the refrigeration device features twointakes 15 and 16 that lie next to each other parallel in a plane and atwhich ventilators are disposed that are not represented, by means ofwhich the external air is drawn into two separate chambers 19 and 20corresponding to the arrows 17 and 18, whereby the two chambers 19 and20 are separated from each other by means of partition 21.

Adjacent to the two chambers 19 and 20 is a Peltier plate disposed thatcontains a multitude of individual Peltier elements that are equipped onboth sides with heat exchanger elements. The Peltier plate 22 isdisposed in the middle of height H and divides in its area therefrigeration device into a first channel 23 and second channel 24. Thechannel 23 is connected with the space 19, whereby the guiding plate 25in connection with the partition 21 assures that the air entering bymeans of the opening 15 enters only into the first channel 23. In acorresponding manner the second space 20 is connected by means of aguiding plate 26 with the channel 24 so that air that is drawn in bymeans of the intake 16 streams only through the channel 24.

The first channel 23 ends at an exhaust opening 27 facing the frontwhile the second channel 24 ends at one or several exhaust openings 28that are provided at an upper or lower side of the refrigeration devicedepending on the installation location. In other words the device can beinstalled in such a manner that the cooling air is blown out upward ordownward. The exhaust opening 18 can extend over the entire breadth ofthe device. It can however also feature other dimensions and therebyblow cooling air better aimed and in a more concentrated manner atpredetermined locations.

The exhaust 27 is aligned during installation in the refrigerationdevice in a switch box according to FIG. 1 with an opening 29 in a backwall 30, while the opening 28 of the second channel 24 is aligned towardthe interior space of the switch box 1.

The Peltier plate 22 features during active Peltier operation a hot sideand a cold side. During active cooling operation the electrical voltageis applied to the Peltier elements in such a manner that the hot sidepoints to channel 23 and the cold side to channel 24.

The device can be operated, as mentioned, in two modes of operation. Inthe first mode of operation it works as pure air circulation. In sodoing the ventilator at the intake 15 can be switched off and only theventilator at intake 16 can be operated. Air is then drawn,corresponding to the arrows 18 at the intake 16, into the chamber 20 andblown by means of the channel 24 to the exhaust 28. In so doing externalair is drawn in through slits and other openings of the switch box andblown by conventional means into the interior space where it can flowout through openings that are not represented.

If the temperature of the external air is so high that sufficientcooling cannot be attained, the Peltier plate 22 or its Peltier elementsare switched to active mode and the ventilator at the intake 15 isswitched on. The air drawn in by means of the intake 16 passescorresponding to the arrows 18 across the actively cooled side of thePeltier plate 22 in the channel 24 and is blown out at the exhaust 28.The air drawn in by means of the intake 15 flows along the arrows 17 onthe hot side of the Peltier plate 22 and discharges the heat there bymeans of the exhaust opening 27, whereby this air is transported to theoutside by means of the opening 29 on the backwall 30 of the switch box.

FIG. 3 shows a plan view of the partially opened refrigeration device,whereby here also the ventilators have been left off. One recognizes thetwo openings 15 and 16 to the chambers 19 and 29, the partition 21 thatseparates the two chambers 19 and 20, and the guiding plates 25 and 26that guide the respective air streams 17 and 18 (compare FIGS. 4 and 5)onto the two sides of the Peltier plate 22. One furthermore sees theexhaust opening 28 of the channel 24.

FIG. 4 presents a cut along the line A-A that indicates more clearly howthe air stream gets along the arrows 18 from the intake 16 by means ofthe first ventilator 32 into the chamber 20 and the guiding plate 26into the channel 24 and from there to exhaust opening 28.Correspondingly FIG. 5 shows in a cut along the line B-B the air streamalong the arrows 17, by means of the intake 15, a second ventilator 33,the chamber 19 and the channel 23 to the exhaust opening 27 along theother side of the Peltier plate 22.

1. Refrigeration device for electronic components with a plate that isequipped on both sides with heat exchanger elements, along whose surfacetwo separate air stream paths are disposed, of which one guides externalair and one internal air, characterized in that the refrigeration devicefeatures two intakes, which lie in one plane, that are in a flowconnection with two separated chambers, that the two chambers are in aflow con-nection by means of guiding plates with channels on the upper-and lower side of the plate, that the plate features at least onePeltier element.
 2. Refrigeration device according to claim 1,characterized in that it is adapted in regard to its outer dimensions asa slide-in for a norm switch box with a norm height unit. 3.Refrigeration device according to claim 1, characterized in that achannel is connected with an exhaust opening on the front face and theother channel is in a flow connection with an exhaust opening disposedon an upper- or lower side of the device.
 4. Refrigeration deviceaccording to claim 3, characterized in that the other channel has itsexhaust opening aligned upward or downward depending on the installationlocation of the refrigeration device.
 5. Refrigeration device accordingto claim 2, characterized in that a channel is connected with an exhaustopening on the front face and the other channel is in a flow connectionwith an exhaust opening disposed on an upper- or lower side of thedevice.
 6. Refrigeration device according to claim 5, characterized inthat the other channel has its exhaust opening aligned upward ordownward depending on the installation location of the refrigerationdevice.